G5 Scratch review quiz

What is the main purpose of a variable in Scratch?

• To make the sprite move

• To store and change data when the program is running

• To create a new backdrop

• To control sounds

Answer explanation

In Scratch, a variable is used to store and change data while the program runs, allowing for dynamic interactions and updates. This is essential for tracking scores, user inputs, and other changing information.

If you set a variable score to 0 and then use change score by 5 three times, what will the value of score be?

• 0

• 5

• 15

• 45

Answer explanation

Starting with score = 0, changing it by 5 three times means adding 5 three times: 0 + 5 + 5 + 5 = 15. Therefore, the final value of score is 15.

Which block is used to reset a variable to a specific value?

• set [variable] to [ ]

• change [variable] by [ ]

• join [ ] [ ]

• pick random [ ] to [ ]

Answer explanation

The block 'set [variable] to [ ]' is specifically designed to reset a variable to a defined value. In contrast, 'change [variable] by [ ]' modifies the variable's current value, while the other options serve different functions.

If you have a variable called lives and you want to decrease it by 1 when the sprite touches an enemy, which block should you use?

• set lives to 1

• set lives to 0

• change lives by -1

• join lives and enemy

Answer explanation

To decrease the variable 'lives' by 1 when the sprite touches an enemy, you should use 'change lives by -1'. This directly modifies the value of 'lives' as intended, while the other options do not achieve this.

Which operator block would you use to check if two numbers are equal?

• <

• >

• =

• +

Answer explanation

The correct operator to check if two numbers are equal is '='. This operator compares the values and returns true if they are the same, making it the appropriate choice for equality checks.

What will the block pick random 1 to 10 do?

• Add numbers from 1 to 10

• Always choose number 10

• Choose a random number between 1 and 10

• Multiply numbers from 1 to 10

Answer explanation

The block 'pick random 1 to 10' is designed to select a number randomly from the range of 1 to 10, making 'Choose a random number between 1 and 10' the correct choice. It does not add, multiply, or always select 10.

If x = 4 and y = 3, what is the result of the operator (x * y) + 2?

• 10

• 12

• 14

• 20

Answer explanation

To solve (x * y) + 2, substitute x = 4 and y = 3: (4 * 3) + 2 = 12 + 2 = 14. Thus, the correct answer is 14.

Which block is used in Scratch to make decisions based on a condition?

• forever

• repeat

• if....then

• broadcast

Answer explanation

The 'if....then' block in Scratch is specifically designed to make decisions based on a condition. It allows the program to execute certain actions only if a specified condition is true, making it the correct choice for decision-making.

If you want a sprite to say “Correct!” only when the answer is 5, which condition should you use?

• if answer = 5 then

• if answer > 5 then

• if answer < 5 then

• if answer + 5 then

Answer explanation

The correct condition is 'if answer = 5 then' because it checks for equality. This ensures the sprite only says 'Correct!' when the answer is exactly 5, which is the desired outcome.

What is the difference between if … then and if … then … else in Scratch?

• They are exactly the same

• if … then only checks one condition, while if … then … else allows two outcomes

• if … then … else only works with numbers

• if … then is for loops, while if … then … else is for variables

Answer explanation

The correct choice is that 'if … then' checks one condition, while 'if … then … else' allows for two possible outcomes. This means 'if … then … else' can handle more complex decision-making in Scratch.